Health care utilization and its association with sociodemographic factors among slum‐dwellers with type 2 diabetes in Tabriz, Iran: A cross‐sectional study

Abstract Background and Aims Slums are known as growing underprivileged areas. One of the health adverse effects of slum‐dwelling is health care underutilization. Management of type 2 diabetes mellitus (T2DM) requires an appropriate utilization. This study aimed to investigate the extent of health care utilization among slum‐dwellers with T2DM in Tabriz, Iran, in 2022. Methods We conducted a cross‐sectional study on 400 patients with T2DM living in slum areas of Tabriz, Iran. Sampling was conducted using a systematic random sampling method. A researcher‐made questionnaire was used for data collection. To develop the questionnaire, we used Iran's Package of Essential Noncommunicable (IraPEN) diseases, in which potential needs and essential health care for patients with diabetes and the appropriate time intervals for use are specified. Data were analyzed using SPSS version 22. Results Although 49.8% of patients needed outpatient services, only 38.3% were referred to health centers and utilized health services. The results of the binary logistic regression model showed that women (OR = 1.871, CI 1.170–2.993), those with higher income levels (OR = 1.984, CI 1.105–3.562), and those with diabetes complications (Adjusted OR = 1.7, CI 0.2–0.603) were almost 1.8 times more likely to utilize outpatient services. Additionally, those with diabetes complications (OR = 1.93, CI 0.189–2.031) and those taking oral medication (OR = 3.131, CI 1.825–5.369) were respectively 1.9 and 3.1 times more likely to utilize inpatient care services. Conclusions Our study showed that, although slum‐dwellers with type 2 diabetes needed outpatient services, a small percentage were referred to health centers and utilized health services. Multispectral cooperation is necessary for improving the status quo. There is a need to take appropriate interventions to strengthen health care utilization among residents with T2DM living in slum sites. Also, insurance organizations should cover more health expenditures and provide a more comprehensive benefits package for these patients.

organizations should cover more health expenditures and provide a more comprehensive benefits package for these patients.

K E Y W O R D S
diabetes mellitus, health care utilization, poverty areas, Type 2

| BACKGROUND AND AIMS
A slum is an area that is characterized by deprivation and inequality. 1 In the United Nations' Sustainable Development Goals (UN SDGs), slums are considered a global health priority. 2 Several characteristics of slum-dwelling can negatively affect slum residents' health, including insecure and poor-quality houses, overcrowding, poor access to safe water, poor sanitation, and other infrastructure. 3 Type 2 diabetes mellitus (T2DM), as one of the most common Non-Communicable Diseases (NCDs), is an increasing public health problem worldwide. [4][5][6][7] Risk factors for developing diabetes include obesity, ethnic origin, social inequality, and the geographic distribution of diabetes, which vary in various countries, regions, or cities. 8,9 The number of people living with diabetes globally is projected to rise from about 537 million adults to 643 million and 784 million adults by 2030 and 2045. The large majority of these people will live in low-and middle-income countries. According to International Diabetes Federation (IDF) report, over three in four adults with diabetes live in low-and middle-income countries. 10, 11 The economic burden of T2DM and its complications is substantial in these countries. 12 Due to political, practical, cultural, and social issues, developing countries face difficulties in managing T2DM. 13 Diabetes has become a crucial public health concern in Asian countries, particularly Iran. 14,15 According to the World Health Organization (WHO), 10% of Iran's population had diabetes in 2016. 14,16 The prevalence of diabetes is associated with poor living situations. 17 The odds of inflicting diabetes are higher in poor neighborhoods. 18 Therefore, disadvantaged groups such as slum dwellers are more prone to the prevalence, risk factors, and complications of T2DM. 19 There are some behaviors and conditions that increase the risk of T2DM in slum dwellers. The weighted prevalence of behavioral factors that increase NCDs among slum-dwellers in Kenya were unhealthy diet (57.2%), lack of physical activity (14.4%), tobacco use (12.4%), and alcohol abuse (10.1%). 20 According to a study in Brazil, T2DM prevalence in slum-dwellers was almost two-fold higher than in the general population (10.1% vs. 5.2%). 21 In addition, the disadvantaged groups are more likely not to adhere to standard health care. 22 A study conducted in urban slums in India found that patients with type 2 diabetes had poor medication adherence. 23 Underutilization of health care services is an adverse health outcome arising from slum-dwelling. 3 Despite unfavorable health status and environment and high-level needs for health care, research demonstrated that those living in slum areas were less likely to seek and use health care services than those residing in the cities. 24,25 Slum residents have lower access to health care services for NCDs than their nonslum counterparts. 25 A study in Iran showed that health services utilization among slum-dwellers was not desirable. 26 Results of a study in Tabriz found that medication underutilization due to high costs was higher in slum dwellers than in the general population (7/2% vs. 3/3%). 27 To prevent the worsening of diabetes, and its complications, health care utilization in slum areas is highly important. To the best of our knowledge, there is insufficient study regarding health care utilization and its factors affecting slum dwellers in slum areas in Iran. To this end, this study aimed to examine the extent of health care utilization among slum-dwellers with T2DM in Tabriz, Iran.

| Study design and setting
This cross-sectional study was conducted among slum-dwellers with T2DM in Tabriz, Iran, in 2022. Inclusion criteria were being over 18- year-old and living in slum areas for at least 5 years. We excluded those with other types of diabetes and those with mental disabilities.
Our definition of health care utilization is the use of services and the number of services used.
Tabriz is a metropolis located in northwest Iran with almost two million inhabitants. According to municipal officials, the number of people living in slums in Tabriz

| Sample size and sampling method
According to Cochran's Sample Size Formula 28 (n = Nt2pq/Nd2 + t2pq), with a possible prevalence of 0.50, a confidence level of 95% and the marginal error of 0.05, the sample size was estimated at 374. We extracted the list of T2DM patients from the National Integrated Health System (SIB). Primary patients' characteristics including age, gender, phone/mobile number, and address are recorded at SIB. A code is assigned to each patient at SIB. We first stratified patients based on gender and 10-year-old groups. Then, nearly 100 patients were selected for each health complex using a systematic random sampling method. In this way, the population size was divided by the desired sample size. This fixed interval was used to select the patients. Finally, 400 patients were included and interviewed in our study.

| Data collection tools
A researcher-made questionnaire was used for data collection. To design the questionnaire, we identified potential needs and essential health care for patients with diabetes and the appropriate time care as well as mental health services. 29 In 2014, the Health Transformation Program was launched to protect people from high medical costs, increase access to health care, and improve health care quality. 30 The questionnaire encompasses two parts. The first part was related to demographic and socioeconomic variables such as age, gender, education status, marital status, income level, insurance coverage status, disease duration, treatment type, and complications (11 questions). The second part was related to questions on health services utilization (6 questions) (see Supporting Information: Appendix). Ten experts in the field assessed the questionnaire's face validity. They confirmed that the questionnaire covered the study's objectives. Data were collected via face-to-face interviews in a confidential setting within the health centers for 2 months. Those who were literate filled in the questionnaire. For those who were illiterate, the questions were read out to them by the two trained researchers and were asked to answer each question. We trained data collectors not to ask directional questions. As a result, we were relatively confident that the study was not biased. Because of the specific process of data collection and the low probability of data loss, our approach for missing data was to exclude cases pairwise.

| RESULTS
A total of 400 slum-dwellers with T2DM were included in our study.
More than half of the participants were female (53.8), and most of them were below the age of 60 years. Ninety percent of participants were married, and almost 60% of them were illiterate or were able to read and write only. The majority of respondents (75.8%) had an income level of 1 < 40 million Rial. The majority of patients (82.3%) were covered by basic health insurance, and only 15% were covered by supplemental insurance. Moreover, the disease duration of most participants was >5 or 5-10 years. Approximately 60% of subjects took oral medication, and more than 70% had complications ( Table 1). Table 1 outpatient services utilization was significantly associated with income level (p < 0.0001), basic insurance (p = 0.014), type of insurance, supplemental insurance (p = 0.02), treatment type (p = 0.001), and diabetes complications (p < 0.0001).

As shown in
Those with higher income levels, who were covered by social and supplemental insurance, those who modified their lifestyle, and those with diabetes complications were more likely to utilize outpatient services. We also found that age (p < 0.0001), education level (p < 0.0001), disease duration (p = 0.0001), treatment type (p < 0.0001), and diabetes complications (p < 0.0001) were significantly associated with inpatient care utilization. Older and illiterate patients, those with disease duration between 5 and 10 years, those with mixed regime simultaneously, and those with diabetes complications were more likely to utilize inpatient care. were referred to health centers and utilized health services during the past 4 weeks. Additionally, 38% out of 39.5% of patients who needed inpatient care services, were referred to health centers and utilized these services in the last year (Table 2).
We applied a binary logistic regression model for the dependent variables (utilization = 0, nonutilization = 1). Based on Hosmer and Lemeshow test, the logistic model was suitable  (Table 3).
we used a generalized linear model to predict variables that influence the number of outpatient and inpatient utilization. Table 4 shows the results of the generalized linear model. Those with diabetes complications, especially those with comorbidities, were more likely to utilize outpatient services (p < 0.001). Additionally, those taking oral medication (p < 0.001) and those with diabetes complications (p < 0.001) were more likely to utilize inpatient care services (Table 4).
T A B L E 1 Demographic and socioeconomic characteristics of the study population and its association with service utilization. Although income was a determinant factor in outpatient service utilization, most patients in our study had a low-income level. A small increase in income level can lead to an increase in outpatient services utilization. This result is supported by previous studies that the leading cause of forgoing care among T2DM was financial constraints. 40 On the contrary, our results did not show a significant association between income level and inpatient care utilization. This might be due to some reasons. Inpatient services are more inelastic, and patients have to use them for survival. Additionally, insurance's copayment for inpatient services is <10% versus 30%-50% for outpatient services.
We also found that patients with a university education were more likely to use outpatient services, while those with low T A B L E 2 Utilization of outpatient services and inpatient care.

CONFLICT OF INTEREST STATEMENT
The authors declare no conflict of interest.

DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available from the corresponding author upon reasonable request.

ETHICS STATEMENT
This study was approved by the Ethics Committee of the Tabriz University of Medical Science (Reference No: IR.TBZME-D.REC.1400.961). Informed written consent was obtained from participants. Researchers read out an informed consent form for illiterate patients and obtained informed written consent from their legal guardians. Participants were assured that their personal information would remain confidential.

TRANSPARENCY STATEMENT
The lead author Masumeh Gholizadeh affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.